<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="index.jsp" method="get">
    <input type="text" name="city" placeholder="请输入城市...">
    <button name="query_btn" type="submit">提交</button>
</form>
</body>
</html>